Category:Vertical Section of Sets

This category contains results about Vertical Section of Sets.

Let $X$ and $Y$ be sets.

Let $E \subseteq X \times Y$.

Let $x \in X$.

We define the $x$-vertical section $E_x$ of $E$ by:

$E_x = \set {y \in Y : \tuple {x, y} \in E}$